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Urbanization processes in Asia are still ongoing; thus, aggregate demand is expected to increase in following years. Even though construction and demolition waste is a source for secondary building materials in industrialized countries, it is not yet an alternative construction material source in Vietnam as the urbanization process is still ongoing. Thus, there is a need for river sand and aggregates alternatives in concrete, namely manufactured sand (m-sand) from primary solid rock materials and secondary waste materials. The focus in the present study for Vietnam was on m-sand sand as alternative for river sand, and different ashes as alternatives for cement in concrete. The investigations comprised concrete lab tests according to the formulations of concrete strength class C 25/30 in accordance with DIN EN 206, followed by a lifecycle assessment study in order to identify the environmental impact of the alternatives. In total 84 samples were investigated, consisting of 3 reference samples, 18 samples with primary substitutes, 18 samples with secondary substitutes, and 45 samples with cement substitutes. This kind of holistic investigation approach comprising material alternatives and accompanying LCA was the first study for Vietnam, and even for Asia, and represents a substantial added value for future policy development in order to cope with resource scarcity. The results show that with the exception of metamorphic rocks, all m-sands meet the requirements for quality concrete. In terms of cement replacement, the mixes showed that a higher percentage of ash reduces the compressive strength. The compressive strength values of the mixes with up to 10% coal filter ash or rice husk ash were equivalent to the C25/30 standard concrete formulation. Higher ash contents up to 30% lead to the reduction of the concrete quality. The LCA study's results highlighted the better environmental footprints across environmental impact categories in the 10% substitution material in comparison to the use of primary materials. The LCA analysis results showed that cement as a component in concrete holds the highest footprint. The use of secondary waste as alternative for cement provides significant environmental advantage.
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Lead (Pb) is one of the toxins responsible for the deterioration of ecological health in aquatic environments. The present study investigated the effects of Pb(NO3)2 toxicity on growth, blood cell morphology, and the histopathology of gills, liver, and intestine of juvenile Nile tilapia, Oreochromis niloticus. A 30-day long aquarium trial was conducted by assigning three treatment groups T1 5.20 mg L-1, T2 10.40 mg L-1, and T3 20.80 mg L-1, and a control 0 mg L-1 following the 96 h LC50 of 51.96 mg L-1 from acute toxicity test. Overall growth performance significantly declined in all the Pb(NO3)2 treated groups and the highest mortality was recorded in T3. Behavioural abnormalities were intense in all the treatment groups compared to the control. Hepatosomatic index (HSI) values were reported as higher in treatment groups. Reduced nucleus diameter and nuclei size in erythrocytes were reported for T2 and T3 groups. Dose-dependent histological alterations were visible in the gills, liver, and intestine of all the Pb(NO3)2 treated groups. The width of the intestinal villi was highly extended in T3 showing signs of severe histological alterations. In conclusion, Pb toxicity causes a negative effect on growth performance, erythrocyte morphology, and affected the vital organs histomorphology of juvenile O. niloticus.
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PURPOSE: Navigational strategies create a scenario whereby percutaneous needle-based interventions of the liver can be guided using both pre-interventional 3D imaging datasets and dynamic interventional ultrasound (US). To score how such technologies impact the needle placement process, we performed kinematic analysis on different user groups. METHODS: Using a custom biopsy phantom, three consecutive exercises were performed by both novices and experts (n = 26). The exercise came in three options: (1) US-guidance, (2) US-guidance with pre-interventional image-registration (US + Reg) and (3) US-guidance with pre-interventional image-registration and needle-navigation (US + Reg + Nav). The traveled paths of the needle were digitized in 3D. Using custom software algorithms, kinematic metrics were extracted and related to dexterity, decision making indices to obtain overall performance scores (PS). RESULTS: Kinematic analysis helped quantifying the visual assessment of the needle trajectories. Compared to US-guidance, novices yielded most improvements using Reg (PSavg(US) = 0.43 vs. PSavg(US+Reg) = 0.57 vs. PSavg(US+Reg+Nav) = 0.51). Interestingly, the expert group yielded a reversed trend (PSavg(US) = 0.71 vs PSavg(US+Reg) = 0.58 vs PSavg(US+Reg+Nav) = 0.59). CONCLUSION: Digitizing the movement trajectory allowed us to objectively assess the impact of needle-navigation strategies on percutaneous procedures. In particular, our findings suggest that these advanced technologies have a positive impact on the kinematics derived performance of novices.
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Agulhas , Cirurgia Assistida por Computador , Computadores , Humanos , Imagens de Fantasmas , Cirurgia Assistida por Computador/métodos , Ultrassonografia , Ultrassonografia de Intervenção/métodosRESUMO
PURPOSE: To investigate the time and effort needed to perform vertebral morphometry, as well as inter-observer agreement for identification of vertebral fractures on vertebral fracture assessment (VFA) images. METHODS: Ninety-six images were retrospectively selected, and three radiographers independently performed semi-automatic 6-point morphometry. Fractures were identified and graded using the Genant classification. Time needed to annotate each image was recorded, and reader fatigue was assessed using a modified Simulator Sickness Questionnaire (SSQ). Inter-observer agreement was assessed per-patient and per-vertebra for detecting fractures of all grades (grades 1-3) and for grade 2 and 3 fractures using the kappa statistic. Variability in measured vertebral height was evaluated using the intraclass correlation coefficient (ICC). RESULTS: Per-patient agreement was 0.59 for grades 1-3 fracture detection, and 0.65 for grades 2-3 only. Agreement for per-vertebra fracture classification was 0.92. Vertebral height measurements had an ICC of 0.96. Time needed to annotate VFA images ranged between 91 and 540 s, with a mean annotation time of 259 s. Mean SSQ scores were significantly lower at the start of a reading session (1.29; 95% CI: 0.81-1.77) compared to the end of a session (3.25; 95% CI: 2.60-3.90; p < 0.001). CONCLUSION: Agreement for detection of patients with vertebral fractures was only moderate, and vertebral morphometry requires substantial time investment. This indicates that there is a potential benefit for automating VFA, both in improving inter-observer agreement and in decreasing reading time and burden on readers.
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Fraturas da Coluna Vertebral , Absorciometria de Fóton , Humanos , Vértebras Lombares/lesões , Variações Dependentes do Observador , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras TorácicasRESUMO
The south-east coast, specifically the Cox's Bazar region, of Bangladesh has achieved a tremendous impetus for producing a large volume of dried fish by involving thousands of marginalized coastal people. This study aimed to assess the socio-economic profile, livelihood strategies, and resilience of the communities engaged in fish drying on the south-east coast using a mixed-methods approach and an Analytic Hierarchy Process (AHP). The study's findings revealed that communities involved in drying were socio-economically undeveloped due to their lower literacy, unstable incomes, and labor-intensive occupations. Apart from notable child labor employed in fish drying in Nazirertek, female workers had relatively higher participation than males. Nevertheless, the female workers had less control over their daily wages and reported working at USD 3.54-5.89 per day, which was relatively lower than male workers who received USD 4.15-8.31 per day. Through fish drying activities, very few workers, producers, and traders were found to be self-reliant. In contrast, the livelihoods of the workers were not as secure as the processors and traders. In addition to suffering from various shocks and constraints, dried fish processors and workers, dried fish traders, off-season income, an abundance of fish species, fish drying facilities, trader's association, and social interrelationship played a significant role in maintaining community resilience. The study recommends appropriate interventions to alternative income diversification options, strong collaboration between communities, local authorities, and government for sustainable livelihoods and better community resilience.
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Renda , Ocupações , Animais , Bangladesh , Criança , Feminino , Peixes , Humanos , Masculino , Estações do AnoRESUMO
OBJECTIVE: There are two distinct approaches for the assessment of left ventricular (LV) dyssynchrony by myocardial perfusion scintigraphy (MPS). The aim of this study was to compare the performance of the count-based and geometrical approach in clinical data using gated single photon emission computed tomography MPS. MATERIAL AND METHODS: Group 1 consisted of 113 patients (49 men, 64 women) with normal perfusion [summed rest score (SRS)≤3], normal LV ejection fraction (≥55%), and normal QRS duration (QRSd<120 ms). Group 2 consisted of 89 heart failure patients (79 men, 10 women) with no restriction for SRS, LV ejection fraction ≤35%, and QRSd ≥120 ms. All MPS parameters were obtained from the software Corridor4DM. Dyssynchrony parameters used were time to peak contraction, SD, and bandwidth (BW). RESULTS: SD and BW were estimated higher (difference group 1: SD 3.0±2.3 and BW 11.3±9.3, P-values <0.001; difference group 2: SD 2.4±4.3 and BW 1.3±17.0, P-value <0.001 and 0.479 respectively) using the count-based approach in comparison with the geometrical method. A significant and good correlation was found between these two methods (R=0.763, 0.902, 0.896 for time to peak contraction, SD, and BW respectively, P-values ≤0.001). SD and BW in both approaches were equally good parameters for differentiating heart failure patients (area under the curve: 0.995-0.998), although using different cut-off values. CONCLUSION: The count-based approach generally provides a wider phase distribution and subsequently greater SD and BW estimates compared with the geometrical algorithm. These differences result in clinically relevant deviations in normal and cut-off values that have to be recognized when evaluating patients.
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Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca/métodos , Imagem de Perfusão do Miocárdio/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Idoso , Algoritmos , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Estudos Retrospectivos , Volume Sistólico , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
CONTEXT: Mitotane [1-(2-chlorophenyl)-1-(4-chlorophenyl)-2,2-dichloroethane] is the first-line treatment for metastatic adrenocortical carcinoma (ACC) and is also regularly used in the adjuvant setting after presumed complete removal of the primary tumor. Mitotane is considered an adrenolytic substance, but there is limited information on distinct effects on steroidogenesis. However, adrenal insufficiency and male hypogonadism are widely recognized side effects of mitotane treatment. OBJECTIVE: Our objective was to define the impact of mitotane treatment on in vivo steroidogenesis in patients with ACC. SETTING AND DESIGN: At seven European specialist referral centers for adrenal tumors, we analyzed 24-h urine samples (n = 127) collected from patients with ACC before and during mitotane therapy in the adjuvant setting (n = 23) or for metastatic ACC (n = 104). Urinary steroid metabolite excretion was profiled by gas chromatography/mass spectrometry in comparison with healthy controls (n = 88). RESULTS: We found a sharp increase in the excretion of 6ß-hydroxycortisol over cortisol (P < 0.001), indicative of a strong induction of the major drug-metabolizing enzyme cytochrome P450 3A4. The contribution of 6ß-hydroxycortisol to total glucocorticoid metabolites increased from 2% (median, interquartile range 1-4%) to 56% (39-71%) during mitotane treatment. Furthermore, we documented strong inhibition of systemic 5α-reductase activity, indicated by a significant decrease in 5α-reduced steroids, including 5α-tetrahydrocortisol, 5α-tetrahydrocorticosterone, and androsterone (all P < 0.001). The degree of inhibition was similar to that in patients with inactivating 5α-reductase type 2 mutations (n = 23) and patients receiving finasteride (n = 5), but cluster analysis of steroid data revealed a pattern of inhibition distinct from these two groups. Longitudinal data showed rapid onset and long-lasting duration of the observed effects. CONCLUSIONS: Cytochrome P450 3A4 induction by mitotane results in rapid inactivation of more than 50% of administered hydrocortisone, explaining the need for doubling hydrocortisone replacement in mitotane-treated patients. Strong inhibition of 5α-reductase activity is in line with the clinical observation of relative inefficiency of testosterone replacement in mitotane-treated men, calling for replacement by 5α-reduced androgens.
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3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Carcinoma Adrenocortical/tratamento farmacológico , Citocromo P-450 CYP3A/metabolismo , Mitotano/efeitos adversos , Mitotano/uso terapêutico , Adolescente , Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/urina , Carcinoma Adrenocortical/metabolismo , Carcinoma Adrenocortical/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Androgênios/administração & dosagem , Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Necessidades e Demandas de Serviços de Saúde , Terapia de Reposição Hormonal/métodos , Terapia de Reposição Hormonal/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Medicina de Precisão/métodos , Regulação para Cima/efeitos dos fármacos , Adulto JovemRESUMO
Circadian biology assumes that biological rhythms maximize fitness by enabling organisms to coordinate with their environment. Despite circadian clocks being such a widespread phenomenon, demonstrating the fitness benefits of temporal coordination is challenging and such studies are rare. Here, we tested the consequences--for parasites--of being temporally mismatched to host circadian rhythms using the rodent malaria parasite, Plasmodium chabaudi. The cyclical nature of malaria infections is well known, as the cell cycles across parasite species last a multiple of approximately 24 h, but the evolutionary explanations for periodicity are poorly understood. We demonstrate that perturbation of parasite rhythms results in a twofold cost to the production of replicating and transmission stages. Thus, synchronization with host rhythms influences in-host survival and between-host transmission potential, revealing a role for circadian rhythms in the evolution of host-parasite interactions. More generally, our results provide a demonstration of the adaptive value of circadian rhythms and the utility of using an evolutionary framework to understand parasite traits.
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Relógios Circadianos , Fotoperíodo , Plasmodium chabaudi/fisiologia , Plasmodium chabaudi/efeitos da radiação , Doenças dos Roedores/parasitologia , Animais , Evolução Biológica , Ritmo Circadiano , Aptidão Genética , Interações Hospedeiro-Parasita , Luz , Malária/parasitologia , Malária/transmissão , Masculino , Camundongos , Reprodução , Doenças dos Roedores/transmissãoRESUMO
PURPOSE: The purpose of this study was to compare contrast-enhanced MRI and nuclear imaging with (99m)Tc-tetrofosmin and (18)F-fluorodeoxyglucose ((18)F-FDG) single photon emission computed tomography (SPECT) for assessment of myocardial viability. METHODS: Included in the study were 60 patients with severe ischaemic left ventricular (LV) dysfunction who underwent contrast-enhanced MRI, (99m)Tc-tetrofosmin and (18)F-FDG SPECT. Myocardial segments were assigned a wall motion score from 0 (normokinesia) to 4 (dyskinesia) and a scar score from 0 (no scar) to 4 (76-100% transmural extent). Furthermore, (99m)Tc-tetrofosmin and (18)F-FDG segmental tracer uptake was categorized from 0 (tracer activity >75%) to 3 (tracer activity <25%). Dysfunctional segments were classified into viability patterns on SPECT: normal perfusion/(18)F-FDG uptake, perfusion/(18)F-FDG mismatch, and mild or severe perfusion/(18)F-FDG match. RESULTS: Minimal scar tissue was observed on contrast-enhanced MRI (scar score 0.4+/-0.8) in segments with normal perfusion/(18)F-FDG uptake, whereas extensive scar tissue (scar score 3.1+/-1.0) was noted in segments with severe perfusion/(18)F-FDG match (p < 0.001). High agreement (91%) for viability assessment between contrast-enhanced MRI and nuclear imaging was observed in segments without scar tissue on contrast-enhanced MRI as well as in segments with transmural scar tissue (83%). Of interest, disagreement was observed in segments with subendocardial scar tissue on contrast-enhanced MRI. CONCLUSION: Agreement between contrast-enhanced MRI and nuclear imaging for assessment of viability was high in segments without scar tissue and in segments with transmural scar tissue on contrast-enhanced MRI. However, evident disagreement was observed in segments with subendocardial scar tissue on contrast-enhanced MRI, illustrating that the nonenhanced epicardial rim can contain either normal or ischaemically jeopardized myocardium.
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Meios de Contraste/farmacologia , Fluordesoxiglucose F18/farmacologia , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , Compostos Organofosforados/farmacologia , Compostos de Organotecnécio/farmacologia , Compostos Radiofarmacêuticos/farmacologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Cardiologia/métodos , Feminino , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/química , Compostos de Organotecnécio/química , Compostos Radiofarmacêuticos/química , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico por imagemRESUMO
BACKGROUND: A multicenter intercomparison assessment was made of the variation in left ventricular (LV) volumes and ejection fractions (EFs) obtained from gated myocardial perfusion single photon emission computed tomography (SPECT) of the 3-dimensional AGATE (Amsterdam gated) cardiac phantom. METHODS AND RESULTS: The phantom was configured to produce 3 different standard end-systolic volume and end-diastolic volume combinations (50 mL and 120 mL, 90 mL and 160 mL, and 120 mL and 190 mL) with corresponding EF (58%, 44%, and 37%). Quantitative gated myocardial perfusion SPECT was performed with 39 SPECT systems in 35 departments. In the multicenter study, for all 3 filling conditions, a wide range of results was obtained. The EF was overestimated (by 1% to 15%), and both the end-systolic volume and end-diastolic volume were underestimated (by 1 to 65 mL). The extent of overestimation of EF was related to the extent of underestimation of the volumes and was independent of filling condition. The trend in error per center was comparable for all 3 filling conditions. Acquisition time per projection was the only independent predictor of the difference between measured and expected EF (P = .0001). CONCLUSIONS: Care should be taken before extrapolation of published and accepted cutoff values for LV EF and volumes in clinical decision making. Results should be validated in each center and monitored for accuracy and consistency over time.